#include<stdio.h>

int main(){
    char ch;
    int lower[26] = {0};

    while(scanf("%c", &ch) != EOF){
        if(ch >= 'a' && ch <= 'z'){
            lower[ch - 97]++;
        }
    }
    
    for(int i = 0; i < 26; i++){
        if(lower[i] != 0)
            printf("%c:%d\n",i + 97,lower[i]);
    }
    return 0;
}

/*统计一篇英文文章里所有小写字母各出现了几次。*/